]> git.ipfire.org Git - thirdparty/systemd.git/blobdiff - src/core/selinux-access.c
Merge pull request #2495 from heftig/master
[thirdparty/systemd.git] / src / core / selinux-access.c
index 5e9a4a5e02c6aaee3537a14e81cdf4bd56943c36..2cdfcf7b5d1ab3ef52308b979f1fe37b8e769305 100644 (file)
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
 /***
   This file is part of systemd.
 
 
 #ifdef HAVE_SELINUX
 
-#include <stdio.h>
 #include <errno.h>
-#include <selinux/selinux.h>
 #include <selinux/avc.h>
+#include <selinux/selinux.h>
+#include <stdio.h>
 #ifdef HAVE_AUDIT
 #include <libaudit.h>
 #endif
 
 #include "sd-bus.h"
+
+#include "alloc-util.h"
+#include "audit-fd.h"
 #include "bus-util.h"
-#include "util.h"
 #include "log.h"
+#include "path-util.h"
 #include "selinux-util.h"
-#include "audit-fd.h"
+#include "stdio-util.h"
 #include "strv.h"
+#include "util.h"
 
 static bool initialized = false;
 
@@ -82,11 +84,19 @@ static int audit_callback(
 
 static int callback_type_to_priority(int type) {
         switch(type) {
-        case SELINUX_ERROR:   return LOG_ERR;
-        case SELINUX_WARNING: return LOG_WARNING;
-        case SELINUX_INFO:    return LOG_INFO;
+
+        case SELINUX_ERROR:
+                return LOG_ERR;
+
+        case SELINUX_WARNING:
+                return LOG_WARNING;
+
+        case SELINUX_INFO:
+                return LOG_INFO;
+
         case SELINUX_AVC:
-        default:              return LOG_NOTICE;
+        default:
+                return LOG_NOTICE;
         }
 }
 
@@ -122,62 +132,44 @@ _printf_(2, 3) static int log_callback(int type, const char *fmt, ...) {
 #endif
 
         va_start(ap, fmt);
-        log_internalv(LOG_AUTH | callback_type_to_priority(type),
-                      0, __FILE__, __LINE__, __FUNCTION__, fmt, ap);
+        log_internalv(LOG_AUTH | callback_type_to_priority(type), 0, __FILE__, __LINE__, __FUNCTION__, fmt, ap);
         va_end(ap);
 
         return 0;
 }
 
-/*
-   Function must be called once to initialize the SELinux AVC environment.
-   Sets up callbacks.
-   If you want to cleanup memory you should need to call selinux_access_finish.
-*/
-static int access_init(void) {
-        int r = 0;
-
-        if (avc_open(NULL, 0))
-                return log_error_errno(errno, "avc_open() failed: %m");
-
-        selinux_set_callback(SELINUX_CB_AUDIT, (union selinux_callback) audit_callback);
-        selinux_set_callback(SELINUX_CB_LOG, (union selinux_callback) log_callback);
-
-        if (security_getenforce() < 0){
-                r = -errno;
-                avc_destroy();
-        }
-
-        return r;
-}
+static int access_init(sd_bus_error *error) {
 
-static int mac_selinux_access_init(sd_bus_error *error) {
-        int r;
+        if (!mac_selinux_use())
+                return 0;
 
         if (initialized)
-                return 0;
+                return 1;
 
-        if (!mac_selinux_use())
-                return 0;
+        if (avc_open(NULL, 0) != 0) {
+                int enforce, saved_errno = errno;
 
-        r = access_init();
-        if (r < 0)
-                return sd_bus_error_set(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to initialize SELinux.");
+                enforce = security_getenforce();
+                log_full_errno(enforce != 0 ? LOG_ERR : LOG_WARNING, saved_errno, "Failed to open the SELinux AVC: %m");
 
-        initialized = true;
-        return 0;
-}
-#endif
+                /* If enforcement isn't on, then let's suppress this
+                 * error, and just don't do any AVC checks. The
+                 * warning we printed is hence all the admin will
+                 * see. */
+                if (enforce == 0)
+                        return 0;
 
-void mac_selinux_access_free(void) {
+                /* Return an access denied error, if we couldn't load
+                 * the AVC but enforcing mode was on, or we couldn't
+                 * determine whether it is one. */
+                return sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to open the SELinux AVC: %s", strerror(saved_errno));
+        }
 
-#ifdef HAVE_SELINUX
-        if (!initialized)
-                return;
+        selinux_set_callback(SELINUX_CB_AUDIT, (union selinux_callback) audit_callback);
+        selinux_set_callback(SELINUX_CB_LOG, (union selinux_callback) log_callback);
 
-        avc_destroy();
-        initialized = false;
-#endif
+        initialized = true;
+        return 1;
 }
 
 /*
@@ -192,8 +184,7 @@ int mac_selinux_generic_access_check(
                 const char *permission,
                 sd_bus_error *error) {
 
-#ifdef HAVE_SELINUX
-        _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+        _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
         const char *tclass = NULL, *scon = NULL;
         struct audit_info audit_info = {};
         _cleanup_free_ char *cl = NULL;
@@ -205,11 +196,8 @@ int mac_selinux_generic_access_check(
         assert(permission);
         assert(error);
 
-        if (!mac_selinux_use())
-                return 0;
-
-        r = mac_selinux_access_init(error);
-        if (r < 0)
+        r = access_init(error);
+        if (r <= 0)
                 return r;
 
         r = sd_bus_query_sender_creds(
@@ -237,7 +225,7 @@ int mac_selinux_generic_access_check(
         if (path) {
                 /* Get the file context of the unit file */
 
-                r = getfilecon(path, &fcon);
+                r = getfilecon_raw(path, &fcon);
                 if (r < 0) {
                         r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to get file context on %s.", path);
                         goto finish;
@@ -245,7 +233,7 @@ int mac_selinux_generic_access_check(
 
                 tclass = "service";
         } else {
-                r = getcon(&fcon);
+                r = getcon_raw(&fcon);
                 if (r < 0) {
                         r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to get current context.");
                         goto finish;
@@ -261,7 +249,7 @@ int mac_selinux_generic_access_check(
         audit_info.path = path;
         audit_info.cmdline = cl;
 
-        r = selinux_check_access((security_context_t) scon, fcon, tclass, permission, &audit_info);
+        r = selinux_check_access(scon, fcon, tclass, permission, &audit_info);
         if (r < 0)
                 r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "SELinux policy denies access.");
 
@@ -276,29 +264,17 @@ finish:
         }
 
         return r;
+}
+
 #else
+
+int mac_selinux_generic_access_check(
+                sd_bus_message *message,
+                const char *path,
+                const char *permission,
+                sd_bus_error *error) {
+
         return 0;
-#endif
 }
 
-int mac_selinux_unit_access_check_strv(char **units,
-                                sd_bus_message *message,
-                                Manager *m,
-                                const char *permission,
-                                sd_bus_error *error) {
-#ifdef HAVE_SELINUX
-        char **i;
-        Unit *u;
-        int r;
-
-        STRV_FOREACH(i, units) {
-                u = manager_get_unit(m, *i);
-                if (u) {
-                        r = mac_selinux_unit_access_check(u, message, permission, error);
-                        if (r < 0)
-                                return r;
-                }
-        }
 #endif
-        return 0;
-}